1. Field of the Invention
The present invention relates to a coil component having a structure of a coil placed around the pillar part of a magnetic core.
2. Description of the Related Art
A coil component having a structure of a coil placed around the pillar part of a magnetic core, such as an inductor or choke coil, generally has metal films at the bottom face of the sheet part of the magnetic core where such magnetic films serve as the base for a pair of external terminals, whereas the spiral part of the coil where a conductive wire is spirally wound is placed around the pillar part of the magnetic core in such a way that one end of the conductive wire is bent downward so that it passes over the sheet part of the magnetic core and then the bent part is joined to one metal film via a solder or other joining material, while the other end of the conductive wire is also bent downward so that it passes over the sheet part of the magnetic core and then the bent part is joined to the other metal film via a solder or other joining material (refer to Patent Literatures 1 and 2).
The bent parts at the one end of the conductive wire and other end of the conductive wire are subject to spring-back (a phenomenon where a reactive force generated by the bent part causes the bending angle to increase after bending). If this spring-back occurs when each bent part is joined to each metal film via a solder or other joining material or when the coil component is soldered to a connection pad of a circuit board, etc., the effective height dimension of the coil component may increase due to the effect of spring-back.
One way to resolve this problem is to adopt a structure whereby each bent part is accommodated within a groove formed on each metal film, but this causes the height dimension of the coil component to increase by the depth of the groove formed on each metal film, and in any event this method does not meet the demand for height reduction in recent years.